I wish the official client just had the ability to let you choose which files to download from a torrent.
I use that feature all the time and yet so few clients support it.
I currently use AZ and have done for years now (never crashed once) and no other client has so far offered that one feature.
I don't need all the features AZ has. All I need is the following:
able to set global up and down speeds
manage all transfers in one window
pause and restart downloads
for the client to not be banned from servers
to be able to choose files individually (preferrably to make absolutely sure it doesn't allocate those files too - AZ sometimes allocates space for file that don't download)
minimal use of resources
So far only AZ satisfies those with the possible exception of the last one but then again I've never seen a Java app on OS X run very well so it might just be the OS X Java VM.
I was looking at the command line rtorrent for OS X, which is a CLI app. I can't find a binary for it and as usual it's not building from source. I came across it looking in this list:
http://en.wikipedia.org/wiki/Comparison_of_BitTorrent_software
Again though, it doesn't seem to support the few features I need.
I wonder why Bittorrent client devs implement features like a 3D transfer view before selective file downloads. Maybe a transfer view gives you something to watch but does it really give you any more info than a list of text?